This study examines whether the addition of a supplemental parent education intervention can increase the effect size of keepin'it REAL, a SAMHSA-model, culturally grounded youth substance use prevention program found to be efficacious among ethnically diverse middle school youth of the Southwest. Family disruption, often a consequence of acculturative adaptation and acculturative stress, frequently operates as a pathway to adverse health outcomes among Latino and other minority families. Reducing risk factors while enhancing protective factors constitutes a known approach to preventing substance use and other risk behaviors. By strengthening family functioning (parental involvement, family support, parental monitoring, and parent-child communication), a supplemental parent intervention can promote effective acculturation and integration into mainstream American social networks. As parents exercise culturally relevant parenting skills that are consistent with promoting their children's health and well-being, they serve as direct sources of influence in reducing their children's substance use risks. The proposed research will adapt a culturally relevant and proven efficacious parenting program for Latino families (Familias Unidas), implement it as a supplement to keepin'it REAL, and compare its effects on family functioning and youth substance use attitudes, norms, and behaviors to two alternate conditions: keepin'it REAL without a parent component and a control condition. Nine Phoenix public schools (3/condition) and 450 families (150/condition) will participate. Following the development and pilot test of the parent component, implementation of the interventions and assessment (pretest and two posttests) will occur in two non-overlapping cohorts of two years each. In addition to assessing the supplemental intervention's efficacy, we will gather information on critical life issues to understand better the challenges to healthy adaptation among diverse Latino families, to test various multivariate models of resilience and healthy adjustment, and to build culturally sensitive theory of adaptive family function and its effects in developing Latino adolescents'skills in avoiding substance use and other risk behaviors. These models and theory can inform the design and implementation of more effective, culturally relevant interventions to avoid familial and individual dysfunction, strengthen families and to reduce health disparities among Hispanic/Latino and other minority families and youth.